Impact press



March 22, 1966 Filed Jan. 14, 1959 L. A. HAUTAU ETAL IMPACT PRESS 2 Sheets-Sheet l INVENTOR. CA/flRLES #4407210 March 22, 1966 A. HAUTAU ETAL IMPACT PRESS 2 Sheets-Sheet 2 Filed Jan. 14, 1959 V 000W W w mo WW4 @w in aw; i LEW United States Patent 3,241,351 IMPAQT PREEQS Llewellyn A. Hautau, 16918 Littlefield, Detroit, Mich;

Charles F. Hautau, 26690 Huntington Road, Huntington Woods, Mich; and Rohert A. Hautau, 2194 Locklin, Pontiac, Mich.

Filed Jan. 14, 1959, Ser. No. 786,826 6 Claims. ((11. 72-429) This invention relates to metalworking presses and more particularly to the impact type of press in which two rams move in opposite directions and simultaneously converge on a workpiece.

Presses which must cut or deform large metal surfaces in a single stroke utilize high forces. In addition to the large physical size of the components which must be used to generate these forces their magnitudes create other problems. One of these is the tendency of the heavy moving masses to generate momentum forces which stress the press frame with respect to its foundation. These stresses cause some small movement of the press, making it difficult to accurately position workpieces and thereby limiting the precision which can be obtained with the press.

Another problem is the distortion of the frame of the press which must absorb most of these forces. The frame distortion also limits the accuracy of the press and the precision of the work which may be formed in it. As the speed of the press increases both the distortion of the frame and the movement of the press frame with respect to the foundations are increased. Therefore the major factor which limits the speed of the press, particularly when it is equipped with automatic work handling equipment, is the magnitude of the press forces.

The present invention contemplates a press in which the forces generated between the press and its foundation are greatly minimized and in which the press frame does not absorb the pressing force.

In order to achieve these objects, the present invention utilizes the impact technique, in which a workpiece, rather than resting on one die half and being hit by the other die half, is simultaneously struck by both die halves from opposite directions. Since the rams to which the die halves are afiixed move in equal and opposite directions their impact forces cancel each other out. These rams are driven by connecting rods which attach to a common crankshaft. Therefore, the forces exerted on the rams are transmitted through the connecting rods to the crankshaft where again they tend to oppose each other. The crankshaft and the connecting rods therefore experience most of the stresses associated with the pressing operation and retain the forces within their own structure. Neither the press frame nor the foundation are subjected to forces of a magnitude comparable with the power of the press.

The freedom from movement and vibration which results from the impact system of the present invention allows the instant press to obtain speeds and accuracies which were only attainable in the prior art through use of press components of a completely uneconomical size. Other objects, applications, and advantages of the present invention will be made apparent by the following detailed description of an embodiment of the invention. The embodiment makes reference to the accompanying drawings in which:

FIG. 1 is a perspective view of the preferred embodiment with certain portions shown cut away.

FIG. 2 is a cutaway perspective view of the driving mechanism of the preferred embodiment.

The press employs a circular central column 10 which 3,241,351 Patented Mar. 22, 1966 ice may be hollow in construction and is preferably formed from rolled and welded sheet steel. At its lower end the central column 10 is aflixed to the top surface of a box generally indicated at 12 which forms the base for the press and also acts as the housing for the ram driving mechanism. The base 12 is formed from a lower half 1 and an upper half 16 which are preferably formed of welded sheet steel and are joined by bolts 18 as may be seen in FIGURE 2. The bolts 18 employ socket heads so that they may be deeply countersunk in holes 2'9 which make connection to the upper surface of the housing half 16.

The lower housing half 14 rests on four pads 22 which level it with respect to the floor. It does not. require any other foundation nor form of connection with the floor.

An upper ram 24 and a lower ram 26 are annular in shape and surround the circular central column 10. Although in the preferred embodiment their central apertures are of such diameter that they surround the central column 10 and do not contact it, in other embodiments of the press they may receive guidance from the central column 10 by means of anti-friction bearings which operate between the column 1% and the inner diameter of the rams 24 and 26.

The upper ram 24 has a plurality of die shoes 28 afiixed to its undersurface. These shoes 28 support upper die halves 30 in a manner similar to those employed in all present presses.

Likewise, the lower ram 26 supports a. group of die shoes 32 at regular intervals about its upper surface. Each of the die shoes 32 is disposed in direct vertical alignment with one of the die shoes 28 which is supported on the upper ram 24. Lower die halves 34 are attached to each of the lower die shoes 32. As will be subsequently described, each of the die pairs 30 and 34- differs from its adjoining pairs in such a manner that a workpiece may be operated upon by a series of the die pairs which perform successive operations upon it to achieve a desired end configuration.

The upper ram 24 is reciprocally driven by four rods 36 (only 3 of which are shown in the FIGURE 1). The rods 36 pass through the ram 24 and are affixed therein. Their upper ends are supported so as to be free for reciprocation in anti-friction gibs 38 which are aflixed in a circular headpiece 40 supported at the upper end of the central vertical column 10. The anti-friction gibs 38 retain the upper ends of the rods 36 in alignment with respect to the frame of the machine. Because of the length of the rods 36 forces exerted on their unsupported lengths might cause them to bend. The lower ends of the rods 36 are driven by a crankshaft in a manner which will be subsequently described.

Intermediate the drive housing 12 and the upper ram 24 the rods 36 pass through circular apertures 42 in the lower ram 26. In the preferred embodiment the rods 36 do not make contact with the sides of the apertures 32 but in other embodiments it would be possible to use anti-friction bearings between the two so as to aid in the support of the rods 36.

The lower ram 26 is similarly driven by four rods 44 (only two of which are shown in FIGURE 1). The upper ends of the rods 44 are supported with freedom for reciprocation in anti-friction gibs 46 which are supported in a workpiece transferring ring 48 which will be described subsequently.

All eight of the rods 36 and 44 pass through antifriction gibs 50 in the top surface of the upper drive housing half 16.

The drive mechanism which reciprocates the rods is powered by an electrical motor 52 of the type having a built-in clutch and brake so that it may be electrically started and stopped very quickly. (The motor 52 is not shown in FIGURE 1 so that other parts of the present embodiment may be seen.) The motor 52 is supported on a shelf 54 which is aflixed to the upper drive assembly cover 16. A pulley and a belt 56 connects the shaft of the motor 52 to a larger pulley 58. A shaft 69 which is afiixed to the pulley 58 is journalled in a bearing 62 retained in a sidewall of the upper drive housing half 16. A spur gear 64 on the other end of the shaft 60 engages a larger gear 66 in such a mannet as to obtain a speed reduction. The gear 66 is in mesh with an identical gear 68 so that both are driven at the same speed.

Each of the gears 66 and 68 is aflixed toand rotates one of a pair of identical crankshafts 7t) and '72. The crankshafts 70 and 72 each have four throws. Two of the throws on each crankshaft are displaced in a first direction while the other two throws are displaced in the opposite direction. Thus, on the crankshaft 72 the throw adjacent to the gear 68 is displaced in an opposite direction to the next throw. Inbetween each throw the shafts are journalled in bearings '74 which are set in partition 76 built in the lower drive assembly housing 14.

Each throw is surrounded by an anti-friction connecting rod bearing 7 8. The bearings each carry clevices which cannot to the lower ends of one of the rods 36 or 44 by means of pins which passes through the clevice and holes in the lower end of the rods. The rods 36 are all connected to throws which are displaced in the same direction. Similarly, the rods 44 are all connected to the oppositely disposed throws. In this manner the rods 36 all move in unison and in direct opposition to the motion of the rods 44 since the two sets of throws are displaced by approximately 180 with respect to each other.

This arrangement causes the rams 24 and 26 to move in opposition to one another so that at one end point of travel the dies almost converge upon one another and at the other end point of travel they are at their widest separation.

The mechanism which powers the material handling of the press that is the section which moves workpieces from position with respect to one die set to the next die position is powered by a gear 80 which drives off the gear 68. A shaft 82 is afiixed to the gear 80 and is journalled in a bearing 84 in the sidewall of the top half 16 of the drive housing. The shaft 82 provides input to an indexing mechanism generally indicated at 86. The function of the index mechanism is to convert the continuous rotary input of the shaft 82 into an intermittent rotary motion of its output shaft 88. While the index mechanism 86 is preferably of the type illustrated in US. Patent No. 2,627,647, it may be any Well known type.

The output shaft 88 of the index mechanism 86 carries a gear 90 which is in mesh with a large ring gear 92 fixed to the workholding ring 48. The gear 92 is rotatably supported on the ring 48 by means of an annular ball bearing 94. Thus the gearing 92 rotates about the ring 48 upon rotation of the upper gear 9t) of the index mechanism 86. Since the index mechanism 86 is powered indirectly from the same motor 52 which powers the reciprocation of the rams 24 and 26, the movement of the gear 92 takes place in timed relationship to the movement of the rams.

A plurality of workholders 96 are disposed on the gear 92 at the same radial interval as the dies and 34 are disposed on their respective rams. In the illustrated embodiment, the workholders, which may be of any well-known configuration, support elongated workpieces 98 into a position of vertical alignment with the dies 30 and 34.

In the operation of the preferred embodiment the motor 52 is in continuous rotation whenever the press is in operation. The clutch and the brake which are associated with the motor 52 are utilized to start and stop the entire operation. The rotation of the motor 52 is transferred through the belt 56 and the pulley 58 to the gears 66 and 68 which rotate their respective crankshafts 7t} and '72. The rotation of the crankshaft causes the rods 36 and 44 to reciprocate. The reciprocation is imparted to the rams 24 and 26.

The rotation of the gear 68 is also transferred through the shaft 82 to the index mechanism 86 which causes its output shaft 88 to rotate. The motion of the output shaft 88 of the index mechanism 86 occurs in such a timed relationship to the movement of the rams 24 and 26 that as the rams converge on one another the gear 92 is stationary. As the rams begin to separate the index mechanism 86 causes the gear 92 to rotate through an arc sufficient to move the workpieces 98 from one station to the next. Then, as the rams 24 and 26 again converge on one another the workpieces 98 are impacted by a die pair 30 and 34 so as to perform a pressing operation upon them. The rams then being to separate and the workpieces move to the next die station, where they are again operated upon. The workholders 96 may be loaded manually or automatically. One die set is empty to allow the loading and unloading to be performed while the gear 92 is stationary.

It is to be understood that other types of workhandling mechanisms than the one disclosed may be used in connection with the present invention. Some workpieces are so shaped that it is not possible to hold them in a clamping means While they are being impacted. Therefore, a workhandling mechanism and die arrangement may be provided in which the workpieces are deposited upon pins which extend above the lower die half. As the rams converge on one another the pins are retracted in the lower die half in such a manner that they become a portion of the lower die surface when the rams meet. After the strike the lower die again descends allowing the pins to support the workpiece, and a hydraulically mechanically operated clamping mechanism may grip the workpiece, lift it off the pins and carry to the next work station.

Having thus described our invention, we claim:

1. In a press, in combination: a central column; a head disposed at one end of said column; a plurality of bushings disposed at spaced points on said head externally of the outer diameter of said column; a reciprocating drive assembly disposed at the other end of said column; a first ram having a central aperture with dimensions greater than the diameter of said column disposed about said column; a second ram having a central aperture with dimensions greater than the diameter of said column disposed about said column; a first set of connecting rods having one of their ends connected to said reciprocating drive assembly and having their other ends disposed in certain of said bushings, and having points along their length connected to the ram adjacent to said head; a support member disposed about said column at a point between said rams; a plurality of bushings disposed at spaced points about said support member radially outward from the outer diameter of said column; and a second series of rods having one of their ends connected to said drive assembly, having their other ends disposed in the bushings in said support member, and having points along their length fixedly attached to such second ram.

2. A press, comprising: a central column; a first ring atfixed to and encircling said column at one extremity thereof; a second ring affixed to and surrounding said column; a plurality of bushings disposed at spaced points in said first and said second rings; a reciprocating drive assembly at the other extremity of said column; a first ram surrounding said column between said first ring and said second ring; a second ram surrounding said column between said second ring and said drive assembly; a

plurality of connecting rods having one of their ends aifixed to said drive assembly and having their other ends extending through said bushings in said first ring, and having points along their length affixed to said first ram; and a second set of connecting rods having one end connected to said drive assembly, having their other ends projecting through said bushings in said second ring and having points along their length affixed to said second ram, whereby said rams are caused to reciprocate in opposed directions.

3. The structure of claim 2 in which said reciprocating drive assembly comprises a source of rotary power and a crankshaft having a first series of throws displaced in a first direction and a second series of throws displaced at 180 degrees with respect to said first throws.

4. A press, comprising: a source of rotary power; a crankshaft rotated by said power source; first and second ram members each having central apertures therein disposed parallel to one another along a single central axis; a plurality of first rods drivingly connected between said first ram and a first plurality of throws on said crankshaft; a plurality of second rods drivingly connected between said second ram and a second plurality of throws on said crankshaft; a plurality of die sets arranged with one die half on each ram at opposed points thereon; a central column passing through the apertures in said first and second rams; and means supported on said column for restricting the motion of said first and second ram members to a direction parallel to the axis of said column.

5. A press, comprising: a pair of similar, annular rams disposed parallel to one another and each having a central aperture therein; a crankshaft; a first plurality of rods connecting said crankshaft to said first ram member; a second plurality of rods connecting said crankshaft to said second ram member, said second plurality of rods passing through apertures in said first ram; a plurality of die sets disposed about the opposed surfaces of said rams with one half of each pair on each ram; a central column passing through the central apertures in said rams; guide means disposed on said column operative to restrain the motion of said rams to a direction parallel to the axis of said column, and Workhandling means disposed on said central column operative to transfer work pieces successively between said die sets; whereby, said rams are reciprocated toward and away from each other in timed relation to the transfer of the workpieces between die sets.

6. In a machine, a base, a column extending from said base, an indexable table fixed to said column at a given point along the longitudinal axis of said column, said given point being spaced from said base, said table being substantially perpendicular to said longitudinal axis of said column, first and second movable platens each having an opening substantially larger than the radial cross section of said column, said first platen being disposed on one side of said table and said second platen being disposed on the other side of said table, said first and second platen being substantially perpendicular to said longitudinal axis of said column, a first group of pistons coupled to said first platen, a second group of pistons coupled to said second platen, said first and second group of pistons being mutually parallel to each other and parallel to said longitudinal axis of said column, said first and second group of pistons being remote from said column and disposed circumferentially about said longitudinal axis of said column, bearing means for maintaining said first and second group of pistons mutually parallel to each other and parallel to said longitudinal axis of said column, driving means coupled to said first and second group of pistons for simultaneously moving said first and second platens alternately toward and then away from said table.

References Cited by the Examiner UNITED STATES PATENTS 593,088 11/1897 Farrar 78-101 1,749,545 3/ 1930 Pierce. 2,232,889 2/ 1941 Spencer 78-22 2,449,365 9/1948 Bober et al 78-42 X 2,449,647 9/ 1948 Fitzgerald 78--42 X 2,475,692 7/1949 Borzym 282 X 2,532,320 12/1950 Maussunest 100264 X 2,550,062 4/1951 Glasner et al. l13--38 2,693,157 11/1954 Georgeff 11338 2,750,909 6/1956 Byerlein 11338 2,767,674 10/1956 Ott 113-38 2,822,696 2/1958 Stacker 11338 2,831,423 4/ 1958 Hautau 100282 X CHARLES W. LANHAM, Primary Examiner.

WILLIAM W. DYER, JR., THOMAS E. BEALL,

Examiners. 

1. IN A PRESS, IN COMBINATION: A CENTRAL COLUMN; A HEAD DISPOSED AT ONE END OF SAID COLUMN; A PLURALITY OF BUSHINGS DISPOSED AT SPACED POINTS ON SAID HEAD EXTERNALLY OF THE OUTER DIAMETER OF SAID COLUMN; A RECIPROCATING DRIVE ASSEMBLY DISPOSED AT THE OTHER END OF SAID COLUMN; A FIRST RAM HAVING A CENTRAL APERTURE WITH DIMENSIONS GREATER THAN THE DIAMETER OF SAID COLUMN DISPOSED ABOUT SAID COLUMN; A SECOND RAM HAVING A CENTRAL APERTURE WITH DIMENSIONS GREATER THAN THE DIAMETER OF SAID COLUMN DISPOSED ABOUT SAID COLUMN; A FIRST SET OF CONNECTING RODS HAVING ONE OF THEIR ENDS CONNECTED TO SAID RECIPROCATING DRIVE ASSEMBLY AND HAVING THEIR OTHER ENDS DISPOSED IN CERTAIN OF SAID BUSHINGS, AND HAVING POINTS ALONG THEIR LENGTH CONNECTED TO THE RAM ADJACENT TO SAID HEAD; A SUPPORT MEMBER DISPOSED ABOUT SAID COLUMN AT A POINT BETWEEN SAID RAMS; A PLURALITY OF BUSHINGS DISPOSED AT SPACED POINTS ABOUT SAID SUPPORT MEMBER RADIALLY OUTWARD FROM THE OUTER DIAMETER OF SAID COLUMN; AND A SECOND SERIES OF RODS HAVING ONE OF THEIR ENDS CONNECTED TO SAID DRIVE ASSEMBLY, HAVING THEIR OTHER ENDS DISPOSED IN THE BUSHINGS IN SAID SUPPORT MEMBER, AND HAVING POINTS ALONG THEIR LENGTH FIXEDLY ATTACHED TO SUCH SECOND RAM. 